School reformers now (and in the past) are (and have been) divided among themselves. Federal, state, and local authorities eager to improve schools often seek similar goals. They want students who are literate, can think clearly, have requisite skills and knowledge to start a career, and contribute to the larger community. Yet these well-intentioned reformers constantlysplit over which of these goals should have precedence and especially, they divide over how to achieve the goals they prize. All of those splits make the business of teacher and school improvement dicey.

That reformers fight among themselves, of course, is hardly new. For generations, educational conservatives have fought progressives over the purposes of schooling, what content and skills had to be taught, how teachers should teach, and how students should learn. Whether it was the 1890s, 1960s, or the 1980s, ruptures between school reformers occurred again and again (see here, here…